utf8mb4 encoding (#7959)

* use utf8mb4 character set for connections to mysql

* use utf8mb4 character set for tables, shorten varchar fields used in unique indexes

* migration type to update table character set

* update table character sets

* set charset for temp_user.status

* gofmt

pkg/services/sqlstore/migrator/postgres_dialect.go

@@ -3,6 +3,7 @@ package migrator
 import (
 	"fmt"
 	"strconv"
+	"strings"
 )
 
 type Postgres struct {
@@ -112,3 +113,13 @@ func (db *Postgres) DropIndexSql(tableName string, index *Index) string {
 	idxName := index.XName(tableName)
 	return fmt.Sprintf("DROP INDEX %v", quote(idxName))
 }
+
+func (db *Postgres) UpdateTableSql(tableName string, columns []*Column) string {
+	var statements = []string{}
+
+	for _, col := range columns {
+		statements = append(statements, "ALTER "+db.QuoteStr()+col.Name+db.QuoteStr()+" TYPE "+db.SqlType(col))
+	}
+
+	return "ALTER TABLE " + db.Quote(tableName) + " " + strings.Join(statements, ", ") + ";"
+}